Mechanical gear drives are known in the most diverse types of constructions. All these gear drives must have a more or less positive or form-locking fit and possess a so-called good "gear stiffness", that is, play or backlash must be avoided. A series of complicated measures have become known hereto, which also lead, to a large extent, to maintenance-free gear drives. However, there is room for improvement with regard to self-adjusting features for avoiding backlash.